RU1825788C - Method of synthesis of benzimidazole-2-yl-methylcarbamate hydrochloride - Google Patents

Abstract

Usage: in the chemical industry SUMMARY OF THE INVENTION: method for producing benzimidazol-2-yl-methyl-carbamate hydrochloride. Reagent 1: hydrogen chloride. Reagent II: benzimidezol-2-yl-methylcarbamate. The process is carried out in an aqueous medium at a molar ratio of reagents of 1.5-2 1 temperature. The desired product is isolated by filtration. Yield 98.5%, basic substance content 98.4%, Purpose: simplification of the process, reduction of energy costs

Description

The invention relates to an improved process for the preparation of benzimidazol-2-yl-methyl carbamate hydrochloride (HCBMK), which is used as an antiseptic and fungicide in agriculture.

The purpose of the invention is to simplify the process, increase the productivity of the reaction volume and reduce energy consumption.

The goal is achieved by the described method for producing HCBMK, which consists in the fact that the interaction of benzimidazol-2-ylmethylcarbamide (BMK) with hydrogen chloride is carried out at a temperature in an aqueous medium at a molar ratio of hydrogen chloride and BMK in the initial mixture of 1.5-2: 1 followed by isolation of the target product by filtration.

When using a smaller excess of hydrogen chloride, the yield of the product and its content of ocnot south substance are reduced.

The filtrate formed after isolation of the product is used as the aqueous medium. The filtrate is returned to the process, and the wet HCBMK is suitable for use as a commercial product. When the filtrate is recycled, u1 calculated quantities of hydrochloric acid are added to achieve the above ratio of BMK to distilled water (condensate) The process under the conditions of the described method / proceeds 15 min

PRI me R 1 (prototype). I use a 1.5 liter capacity reactor equipped with a jacket to provide heat, a stirrer, a reflux condenser and a dispenser

625 g of distilled water, 22 g (0.217 mol) of hydrochloric acid and 43 g (0.216 mol) of BMK are charged to the reactor. The reaction mixture is heated to boiling with stirring and allowed to dissolve BMK. The duration of the process is 1.5-2.0 hours.

The reaction mixture was transferred to a vacuum rotary evaporator, 535 g of condensate was distilled off over 1.0-1.5 hours and 115 g (0.213 mol) of wet HCBM were recovered. After drying under an infrared lamp in a fume hood, 58 g (0 213 mol) of dry HCBM are obtained. Yield 9.8.6%, basic substance content 96.6%, humidity 9.6%.

(L

WITH

Found

in wet in dry 6.81

waste / g HCBMK.

13.90 13.79 water

reaction formula

V t

where P is the productivity of the reaction volume;

M is the molar mass of HCBMK;

X is the number of moles of HCBMK in the target product;

V is the reaction volume, l;

g - the duration of the process, h

In example 1, the productivity of the reaction volume is 28 g / l h

Example 2 A reactor similar to that described in Example 1 was used. 624 g of distilled water, 2.6 g (0.223 mol) of hydrochloric acid and 43 g (0.216 mol) of BMK were charged into the reactor.

The molar ratio of HChRMK is -1.03: 1.00.

The reaction mass is stirred for 1 h at 20 ° C and filtered. 19 g of paste with a moisture content of 52.7% and 650 g of a filtrate containing 45J5 g (0.173 mol) (7%) of HCBMC are obtained. After drying the paste under infrared pulp in a fume hood, 9 g of dry HCBMK is obtained. yield 7%. the content of the basic substance is 44.4%,

PRI me R 5. Use a reactor similar to that described in example 1. 547 g of filtrate containing 38.3 g (0.145 mol. 7%) HCBMK and 3.45 g (0.094 mol) of hydrogen chloride are charged into the reactor, 24, 7 g (0.243 mol) of hydrochloric acid, 43 g (0.216 mol) of BMK and 75 g of distilled water.

The molar ratio of H CI: B M To 1.56: 1.00.

The reaction mass at a temperature of 20-22 ° is stirred for 0.4 h and filtered.

120 g of HCBMK paste with a moisture content of 53% are obtained, after drying of which under an infrared lamp in a fume hood 57 g (0.213 mol) of HCBMK are obtained, yield 98.5%, basic substance content 98.3%.

Estimated

13.03 13, G5

Found in wet-in dry haunt 6.53 13.87 13.74

The productivity of the reaction volume is equal to

0

5

0

5

0

0

5

5

0

5

R

0.213 263.7

 209 g / l h

0.67 0.4

There is no waste in the process of production and isolation of HCBMK.

PRI me R 4. Use a reactor similar to that described in example 1.

547 g of filtrate containing 38.3 g (0.145 mol) of HCBMK and 6.85 g (0.178 mol) of hydrogen chloride, 24.9 g (0.246 mol) of hydrochloric acid, 43 g (0.216 mol) of BMC and 75 are charged to the reactor g of distilled water

The molar ratio of HC1: BMK is 2.00: 1.00.

The reaction mass at 18-20 ° C was stirred for 0.35 hours and filtered to obtain 119 g of HCBMK paste with a moisture content of 52% and 549 g of a filtrate containing 38.4 g of HCBMK and 6.87 g of HCI.

After drying the paste under an infrared lamp in a fume hood, 57 g (0.213 mol) of HCBMK are obtained. Yield 98.5%, basic substance content 98.4%.

The performance of the reaction volume is equal to

D 0.213 263.7 0.0,

R But: bT 5 ° G / L H

No waste.

PRI me R 5. Use a reactor similar to that described in example 1,

1100 g of filtrate containing 34.3 g (0.130 mol) of HCBMK and 3.21 g (0.088 mol) of hydrogen chloride, 20.0 g (0.198 mol) of hydrochloric acid, 37.8 g (0.190 mol) of BMC and 82 g of distilled are charged into the reactor. water.

The molar ratio of 1.50: 1.00.

The reaction mass is stirred at 20 ° C for 0.2 h and filtered. Receive 109 g of paste HCBMK moisture content of 53% and 1101 g of a filtrate containing 35.0 g (0.133 mol) HCBMK and 3.2 g of hydrogen chloride. After drying the HCBMK paste under an infrared lamp in a fume hood, 51.0 g (0.186 mol) of HCBMK are obtained, yield 98.0%, basic substance content 96.1%. Analysis Estimated Found

in wet, in dry home

NS,% 13,836.79 14.42

H20,% 13.65-14.20

The performance of the reaction volume is equal to

0.186 -263.7 1.23 -0.2

200 g / l h

Due to the deterioration in the quality of HCBMKs after 50-fold recirculation, the filtrate is regenerated. 1100 g of the filtrate was distilled off on a rotary evaporator. 735 g of condensate are obtained containing 3 g of hydrogen chloride, which is returned to the process to produce HCBMC in place of distilled water, and 300 g of bottoms. The bottom residue is waste and is an aqueous suspension of HCBMK and other impurities that were contained in the starting BMC.

The amount of waste is

0.186 .32 ° 6 ° 3.7. 50 -0.12 g / g HCBMK.

PRI me R 6. Use a reactor similar to that described in example 1. In the reactor load 1 1 TO g of the filtrate containing 77.7 g (0.295 mol) of HCBMK and 3.22 g (0.088 mol) of hydrogen chloride, 20, 1 g (0.199 mol) of hydrochloric acid, 37.8 g (0; 190 mol) of BMK and 82 g of distilled water.

The molar ratio is 1.51: 1.00.

The reaction mass is stirred at 25 ° C for 0.2 h and filtered. Obtain 102 g of paste HCBMK with a moisture content of 51% and 1110 g of a filtrate containing 77.7 g HCBMK and 3.22 g of hydrogen chloride. After drying the HCBMK paste under an infrared lamp in an fume hood, 50.0 g (0.187 mol) of HCBMK are obtained, yield 98.5%. the content of the main substance is 98.4%.

Analysis EstimatedFound

in wet in dry

HCI,% 13,836.7113.92

H20,% 13.65-13.79

The performance of the reaction volume is equal to

R 200 g / l h

0, 263.7 T.23 -0.2 No waste. Example. A reactor similar to that described in Example 1 was used. 550 g of filtrate containing 38.5 g (0.145 mol) of HCBMK and 0.83 g (0.023 mol) of hydrogen chloride, 20.4 g (0.201 mol), 43 were charged into the reactor. g (0.216 mol) of BMC and 77 0 g of distilled water.

The molar ratio of HC1: BMK is 1.03: 1.00.

The reaction mass at a temperature of 20-22 ° is stirred for 1.5 hours and 5 filtered.

118 g of HCBMK paste with a moisture content of 51% and 551 g of a filtrate containing 38.6 g (0.145 mol) of HCBMK and 0.83 g (0.023 mol) of hydrogen chloride are obtained. 0 After drying the HCBMK paste under an infrared lamp in a fume hood, 58 g (0.2 mol HCBMK, yield 93%, basic substance content 91.0%) are obtained.

The implementation of the described method 5 allows to simplify the process of producing benzimidazol-2-ylmethyl carbamate hydrochloride and significantly reduce the energy consumption for its production.

Claims (1)

SUMMARY OF THE INVENTION Method for the preparation of hydrochloride benzimidazol-2-yl-methylcarbamate by the interaction of benzimidezol-2-yl-methyl1sarbamad (BMC) with hydrogen chloride in an aqueous medium, characterized in that, 5 t in order to simplify the process, increase the productivity of the reaction volume and reduce energy costs, the process is carried out at a temperature of 15-25 ° C at a molar ratio of HCI and BMK in the initial 0 mixture (1.5-2.0): 1, followed by isolation of the target product by filtration.